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Atmospheric pressure leaching of nickel from a low-grade nickel-bearing ore

Javanshir S., Mofrad Z. H., Azargoon A.

Physicochemical Problems of Mineral Processing

2018

Vol. 54, iss. 3

890--900

This study focused on the extraction of nickel from a low-grade lateritic ore. The characterization of representative samples was done by X-ray diffraction (XRD), X-ray fluorescence (XRF), and microscopic mineralogical studies. Nickel was uniformly distributed in iron (hydr)oxide minerals. The pre-concentration of nickel was attempted by magnetic separation, but was unsuccessful. The effect of the type of lixiviant, acid concentration, S/L ratio, time, and temperature were investigated in the atmospheric leaching process. Based on the experimental data, optimum conditions for the maximum recovery of nickel were determined under the following conditions: 5 M H2SO4, 25% (w/v), 90 ºC, and two hours. Pre-calcination, for increasing nickel extraction by converting goethite to hematite, was carried out on raw ores at different times (30-180 minutes) and temperatures (180-540 ºC). Recovery was found increasing from 69 to 95% under the same conditions. Kinetic studies were conducted by fitting the data with Shrinking Core (SC) models. The study determined, from the estimate of activation energy, that the rate of reaction controlled by chemical reaction.

Characterization and concentration studies of Jalal Abad iron mine

Hashemi S. A., Rezai B., Tavakoli Mohammadi M. R., Javanshir S.

Archives of Mining Sciences

2013

Vol. 58, no. 3

729--745

Characterization and determination of liberation degree are the first stages of ore dressing. Block 4 of Jalal Abad mine, Kerman province, Iran, has three kinds of iron ores; D1, D2 and D3, with different grades. In this research, chemical analysis, mineralogy, liberation degree and magnetic enrichment studies were done by XRF, XRD, microscopic sections and Davis tube, respectively. The results indicated that D1, D2 and D3 had average iron grades of 58, 52 and 38%, respectively. The minerals of Magnetite, Hematite, Dolomite, Calcite and Quartz were distinguished. Average liberation degree was estimated about 500 μm by Microscopic studies. The results of magnetic tests showed that iron grade of D1, D2 and D3 concentrates increased to 70.46, 63.98 and 45.37%, respectively. The optimization of blending was investigated for production of accumulated concentrate with desirable iron grade (68%) using MATLAB software.

Charakterystyka i określenie stopnia uwalniania to pierwsze etapy w procesie oczyszczania rud. W bloku 4 kopalni rud żelaza Jalal Abad w prowincji Kerman w Iranie, znajdują się trzy rodzaje złóż rud żelaza: D1, D2, D3, różnej klasy. W pracy tej przedstawiono wyniki analizy chemicznej, mineralogicznej, stopnia uwalniania oraz separacji magnetycznej wykonanych przy zastosowaniu metod XRF, dyfrakcji (XRD) oraz metod mikroskopowych i rurki Davisa. Wyniki analiz wskazują, że złoża D1, D2, D3 to złoża w klasie o zawartości odpowiednio 58, 52 i 38%. W próbkach określono zawartość magnetytu, hematytu, dolomitu, kalcytu oraz kwarcu. Średni poziom uwalniania określony przy pomocy metod mikroskopowych oszacowano na 500 μm. Wyniki badań magnetycznych wskazują, że zawartości żelaza w koncentracie D1,D2 i D3 wzrosły odpowiednio do 70.46, 63.98 i 45.37%. Przeprowadzono optymalizację mieszania koncentratów w celu produkcji końcowego koncentratu o pożądanym poziomie zawartości żelaza (68%) przy zastosowaniu oprogramowania MATLAB.